I am using UTMC 1553 protocol chip. All 4 mandatory mode codes are legalised and implemented. On testing we found correct status word is sent by the system for mode code commands, but action is not taking place. For eg. on sending 'transmitter shut down' command, status word is coming, but transmitter shut down is not happening. What may be the reason?
I just had a quick view to the datasheet (UT1553).
You write the shutdown command...can you read it back to verify that it is being accepted?
How exactely do you test whether it is shut down or not?